Some firms will make a living based entirely on mining "data exhaust", the bits and bytes produced by other activities. One example is Google’s PowerMeter, which not only lets users check their use of electricity online but gives Google access to lots of data to analyse and, not least, sell advertisements against.

In Brin’s way of thinking, each of our lives is a potential contribution to scientific insight. We all go about our days, making choices, eating things, taking medications, doing things—generating what is inelegantly called data exhaust.

Merchants have a larger problem when it comes to collecting data about customers. Often, there's just too much information to make any sense out of it, a problem that has spurred interest in analysis software and services to sort through all that data. "The Web and e-mail create a tremendous amount of data exhaust," says Steve Markowitz, CEO of Intellipost Inc. "Anytime you click on a page, data are thrown off. The question is how do you harness data in a fashion that is meaningful."